A quarter of a century after the launch of Acorn User magazine, Drobe has managed to track down one of its most famous contributors: Jan Vibe. Virtually every month during the 1990s, the magazine's cover disc would feature a number of new graphical effects and animations created by Jan. As well as reminiscing about his Mode 15 days to Drobe, he's now pulled together his back catalogue of software, including some previously unseen pieces, and made it freely available for download.

Drobe: Are there any programs you've written that you're particularly proud of?

Jan: "There was one program that I was particularly proud of: it was called 'Tentacles', and I described it as the most disgusting program I have ever made. I think it was published in 1986. The reason for my pride is that this program was very different from most other programs in Star Info. No one had ever tried to publish a visually 'disgusting' program before.

"It also shows that computer programs can be used for creating art, which was something most people I knew, at that time anyway, had trouble grasping."

Would you describe your work as a form of modern art?

"Oh yes. I don't see any difference of making art with a computer, compared to something like painting.

"It is still art. But when I started making those small graphics programs, I often got some remarks about using the computer for something 'useful' instead. Fortunately more and more people now use computers for making art, just see all the CGI movies. So it appears that I was just a little ahead of my time."

What was your favourite effect you created for an Acorn User Star Info program?

"My favourite effect must have been making animations using the shadow screen. I remember making an enormous amount of programs using this effect.

"It was really quite simple, you set up two screen images, and while you made a picture on one screen image, you showed the other, and when the picture was finished, you switched screens. The effect was that you did not see any drawing process on the screen, it looked like the picture was drawn in a fraction af a second.

"My old RiscPC, which I still have, could draw a reasonable amount of screens to make the animation seem fluent."

I seem to recall your fire animations were quite popular.

"There were quite a few. I think the one you refer to is one where I drew some simple pattern in the screen, and then distorted the image using the sprite system, all the while keeping the colours cycling.

"I have just found it, it was in the March 1992 Acorn User issue. Yes, I also have most of the AU issues, although they are placed in my attic now, and no, I won't part with them.

"If I have to pick some over the others, I will say, that the trio of programs in the Christmas 1997 issue, and the Anamorph art program in September 1995, and the tree program in the January 1998 issue."

A lot of the programs rely on mathematics. How did you come up with the equations to calculate the shapes to draw?

"Yes, many of my programs use math to do what they do. Many of them use sin and cos functions. These are nice functions because they are are so easy to configure. Their result lies between -1 and 1, so they are easy to scale too.

"Many people probably look back to those functions with a shudder because they remember endless boring trigonometric calculations from scool. I guess that math looks more exiting when presented this way.

"Many of the really mathematical formulas I used I got from an old formula collection I used in high school. Other formulas, I simply learned about by trial and error."

How did you come up with so many Star Info entries?

"A new program could start out in two ways. Sometimes, I just sat down, entered some very simple program, and started playing around with it. One thing led to another, and eventually the program had mutated into something new. And if it looked interesting enough, I kept it, and tried to improve it.

"The other way a program could start out, was that I would get an idea, usually when I was away from the computer. I would then make a mental note, and when home, would try to create a program that would work using this idea."

"One of the ideas I got was put in a program called 'Shatter'. I once broke a mirror, and looking at the shards, I got the idea of making a program that broke a polygon up like shattered glass. This was one of the most difficult programs I ever wrote.

"The program Mail2 was made for a special reason. In Statistics Denmark, we were going to introduce email to all employees. Obviously, this required a instruction booklet, and I was given the task of making a cover illustration. This was it. And it was accepted.

"Also, Crop2 was inspired by a picture of a crop circle I had seen in a newspaper."

Did you enjoy using lots of little techniques to squeeze the most out of your Acorn computers?

"Yes, doesn't everybody? You ask me as if this was only done in the past, but I still use the techniques I developed on my Acorn computer when solving programming problems today.

"The Acorn computer was my learning lab. Most of what I know about programming, I learned by playing with with BASIC on the Archimedes, and later, the RiscPC computer."

How did you start out writing Star Info programs?

"I started writing Star Info programs simply because I wanted to see if I could get a program published in Acorn User.

"I sent them the Facebender program among others, and I got a very nice letter back. They said that they were impressed with the programs, and they would not put it in Star Info, but instead put it in a special article if I would write it. This I did, of course, and since then, I just sent in the programs I made, which I thought would interest other people."

Do you still write little graphical effect programs?

"I still write graphical programs, but I don't write them in Acorn BASIC anymore. Nowadays, I write them in DarkBasic, which is a very strange BASIC dialect, but it has a full set of DirectX commands, which enables me to make my graphical programs work in a 3D universe.

Jan, a 50-year-old civil servant, has worked as a computer helpdesk consultant for Statistics Denmark for the past 25 years. He said: "Mostly, I work with the Microsoft Office tools, I specialise in Microsoft Word. It may sound boring, but Word can be made to do some very amazing things, if you know how.

"The work is not particularly hard, and I have a lot of freedom, which I use for my interests, which is computing of course, my house, garden and dog, collecting movies, reading a lot, and trying to live a healthy life generally.

"I live in an old house, it is about 250 years old, with a very big garden, so a lot of my spare time is used to keep this house looking nice. It is a nice house, cool at summer, and warm in winter, but it was built for smaller people than I. I have got used to it, but when I have friends visiting, they invariably bang their heads on the beams in the ceiling, 180 cm above the floor."

"You cannot compare this work to my Star Info contributions, though. The colour shifting in BASIC is a programming technique, while my movie on youtube.com was made with a 3D editor, which hides every scrap of code completely. You point and you click. It is more like modelling a scene than programming."

Do you still use your RiscPC?

"No. When Acorn stopped making computers, I gradually stopped using it too. You see, in Denmark, the Acorn computers were quite rare, and very expensive. Also the Microsoft computers were getting cheaper, and faster, and the operating system was becoming more stable.

"I got tired of seeing my friends and colleagues use computers costing only half that of an Acorn computer, with more power, memory, and peripherals. So in 2001, I also bought a Microsoft-powered PC. I still kept the Acorn computer, but I did not use it much. Now I have it as a memento, but it still works perfectly."

What do you think of the new versions of RISC OS and new RISC OS-powered computers?

"The latest RISC OS I have seen is the one installed in my own computer and is from 1996, so I cannot comment on newer OS versions. On the other hand, I do have a Palm, which is driven by an ARM processor. But I do not think this counts."

Gallery
Jan created hundreds of programs and animations using BASIC. Below are just a few of the more colourful and intricate. Click on a thumbnail for a larger view.

Most of the above screenshots were taken using Jan Boer's A310 emulator. The BASIC programs were easily transfered into the emulator from the host side using the EmuTrans program supplied with the emulator - see its documentation for details. Jan's more recent programs, written for the RiscPC specifically, will run on more modern machines.

Thanks drobe for publishing such a great interview. I suspect Jan probably doesn't appreciate quite how inspirational his work was and I'm glad to see he's still creating digital art (any chance of seeing some of his DarkBASIC work?).

I remember showing the result of Tentacles to my girlfriend at the time (I admit a really dumb thing to do). I think it put her off computers for at least a decade!

Jan's contribution to *info was always the highlight of any issue of the Acorn User for me, both for the stunning visuals, and also the code was very instructive, back then before cover discs destroyed the learning process of typing in listings from the yellow pages.

The multi-coloured tentacle screen shot above, doesn't do justice to the original hideous flesh tones, so I've temporarily put up a copy on my web space, along with a port to win 32 which I did before the days of emulators to bring that sense of revulsion to Windows users too (as if using that OS isn't revolting enough). [link]

Good to see the interview with Jan. I went to high school with Jan and we were part of a small community of BBC-micro and later Archimedes users who met regularly. In later years, I haven't had much contact with Jan, but I agree with him that playing around with BBC Basic taught me a lot that I have used later. One of the programs (the planet generator) I offer for download on my homepage ([link]) started out as a short Basic graphics program on my A310, but has been through many generations of updates (and a port to C) since. It should compile under RISC OS, but I haven't tried to do so with recent versions.